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氢能作为一种高焓值的绿色能源在解决未来能源危机和环境污染中备受关注,而铝水反应在众多制氢途径中被认为是最具优势的方法之一。本文着重论述了近几年铝基材料水解制氢技术的研究进展。铝水制氢是一种很有发展前景的储存和运输氢能的方式,但Al表面致密的氧化层阻碍了铝水反应的进行,使其难以在常温常压情况下产生氢气。为充分开发利用氢能源,可采用添加碱、氢化物、金属氧化物、无机盐等方式,或将金属单质与Al通过烧结、熔炼、球磨等先进的技术手段进行复合,能够有效地活化Al,从而实现低环境温度、短诱导时间、快产氢速率、高转化率的铝水反应,为燃料电池电动汽车现场供氢。 相似文献
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铝与烧碱溶液的反应中,H2O和NaOH谁作氧化剂是一直困扰学生学习的一个突出问题,而教学中,铝与水的反应在通常情况下又很难实现,因此,很长一段时间的教学仅停留在理论上的分析。本人通过实验改进与探究,证实铝与烧碱溶液的反应H2O作氧化剂。 相似文献
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采用共沉淀法制备了镁铝类水滑石(Mg-Al-CO3LDH)、镁锌铝类水滑石(Mg-Zn-Al-CO3LDH)和锌铝类水滑石(Zn-Al-CO3LDH),并研究了它们在碳酸二苯酯(DPC)与1,4-丁二醇(1,4-BD)酯交换合成聚碳酸酯二醇(PCDL)反应中的催化活性。在常压反应阶段,以苯酚的产率表征催化剂的活性;在减压缩聚阶段,以产品的数均分子量Mn和羟基值来表征催化剂的活性。结果发现,Zn-Al LDH具有良好的催化活性。在优化反应条件下,获得了Mn和羟基值分别为1600和70.8mg KOH/g的PCDL。 相似文献
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采用共沉淀法制备了以二氧化硅为载体,表面包覆镍铝水滑石的NiAl-LDHs/SiO2复合物,借助XRD、IR及N2吸附-脱附等手段对合成物进行了表征,并将其应用于苯甲醛与乙醇反应生成安息香乙醚反应中进行活性评价。结果表明,复合物中镍铝水滑石与二氧化硅以稳定的Si-O-Al和Si-O-Ni键结合,镍铝水滑石均匀分布于二氧化硅表面,且生成的复合物比表面积较大;当镍铝水滑石负载量为20%时,在反应温度为70℃﹑反应时间为60 min条件下,NiAl-LDHs/SiO2催化苯甲醛与乙醇反应的苯甲醛转化率为61.8%,安息香乙醚选择性接近100%,其催化效果明显优于单一的NiAl-LDHs。 相似文献
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本文从实验实际认真研究了镁与水、铝与水的反应,对高中课本中关于镁与水反应的知识介绍进行了质疑,提出了修订意见。并对镁与氯化铵溶液的反应谈了自己的看法。 相似文献
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纳米晶镁铝水滑石的制备及其热分解机理 总被引:15,自引:0,他引:15
研究了无机阻燃剂镁铝水滑石纳米晶的制备及其热分解机理.采用常压下,一步反应的液相法制备镁铝水滑石试样,用XRD和TEM测试试样的相组成和形貌,针状镁铝水滑石纳米晶体的长度约80 nm.依据DSC和DTA-TG测试结果,发现镁铝水滑石纳米晶的热分解由两个阶段组成:第一个吸热峰出现在220 ℃左右,第二个吸热峰出现在380 ℃左右.研究了反应时间对所得镁铝水滑石试样的热分解性能的影响,发现延长反应时间,镁铝水滑石试样的第一次、第二次热分解的起始温度升高,第一次热分解的失重值增大,最后剩余氧化物的量增大,从而增强镁铝水滑石阻燃剂的阻燃性能.根据不同升温速率下获得的DSC测试数据,应用Achar微分法、Šatava-Šesták积分法和Ozawa积分法对镁铝水滑石纳米晶热分解的第二个阶段进行了动力学计算和分析,确定该段的热分解机理函数积分式为(1-α)-1-1. 相似文献
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乙醇-水介质中氟-铝沉淀电位滴定体系研究 总被引:2,自引:0,他引:2
由于氟-铝的多级络合反应,在水溶液中用氟化物直接滴定铝没有明显的电位突跃,若用乙醇-水介质,则电位突跃明显[1~3].本文对乙醇-水介质中氟-铝沉淀电位滴定体系的化学平衡进行了研究.测定了在不同浓度的乙醇介质中氟-铝的络合比及各级络合物的稳定常数等参数.实验表明用F-电位滴定测定铝可取得较好结果. 相似文献
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V. I. Bol'shakova L. I. Demenkova É. N. Shmidt V. A. Pentegova 《Chemistry of Natural Compounds》1989,24(6):691-694
The compositions of the neutral diterpenoids of the oleoresins of five species of conifers growing in the Transcarpathia have been studied. It has been found that the oleoresins ofAbies alba M.,Larix decidua M., andPicea excelsa L. contain more than 50% of neutral diterpenoids. The group and qualitative compositions of the oxygen-containing diterpenoids have been determined. In the oleoresins ofAbies alba,Picea excelsa, andPicea abies tertiary alcohols — cis-abienol and isocembrol — predominate, while inLarix decidua the main component is the hydroxy ester larixyl acetate. Primary alcohols related to the resin acids have been found in all the oleoresins investigated. Features of the distribution of diterpenoids according to the species of conifers have been revealed. The results obtained are necessary for the chemotaxonomy of conifers of the family Pinceae.Novosibirsk Institute of Organic Chemistry, Siberian Branch, Academy of Sciences of the USSR. Translated from Khimiya Prirodynkh Soedinenii, No. 6, pp. 812–816, November–December, 1988. 相似文献
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利用手持技术改进测定乙醇分子结构实验 总被引:1,自引:0,他引:1
利用压强传感器代替排水集气法,改进测定乙醇分子结构实验的仪器装置,并探索最佳反应条件。另外,设计两个空白实验,结合压强变化曲线对实验误差进行相关讨论。 相似文献
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由于石化行业的生产需要,其材质的使用具有多样性和广泛性,经常会出现顾客委托的测试样品的一个或几个元素跨越光谱仪现有测试程序测量范围的情况。本法通过对光谱仪测试原理的认识,根据光谱仪的测试能力及标样的采集,实现了一个或几个元素测量范围的扩展,并对其测量的影响因素进行了研究。 相似文献
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Effect of the Method of Modification of Zeolite X on Selectivity of Catalytic Methylation of Toluene
Voloshyna Yu. G. Pertko O. P. Patrylak L. K. 《Theoretical and Experimental Chemistry》2019,54(6):395-400
Theoretical and Experimental Chemistry - The effect of the method of modification of catalysts based on zeolite X by cesium and magnesium cations (ion exchange and impregnation) on the selectivity... 相似文献
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The spectral-polarization characteristics of absorption and phosphorescence of molecules of the initial form of nitro-substituted
indolinospirobenzothiopyran were studied in oriented polyethylene films and in solutions with different polarity. An oscillator
model of the electron transitions responsible for the formation of absorption and luminescence spectra was suggested. It was
established that the principal differences in the spectral and photophysical properties of the compound studied and its oxygen-containing
analog are associated with the fact that the electronegativity of the S atom is lower than that of the O atom.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1143–1146, June, 1997. 相似文献
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Influence of viscosity of medium on processes of oxygen quenching of excited states of mesoporphyrin
E. I. Kapinus V. A. Ganzha B. M. Dzhagarov E. I. Sagun V. B. Pavlenko 《Theoretical and Experimental Chemistry》1989,25(2):146-151
The oxygen quenching rate constants for singlet and triplet excited states of the dimethyl ester of mesoporphyrin IX increase with decreasing viscosity of the medium and reach a maximum at a viscosity of approximately 0.4 mPa·sec, after which the rate constants begin to decrease. The drop in rate constant with increasing fluidity of the medium may be related to a nonequilibrium character of the elementary act in the interaction of the reactants in the solvent cage. In viscous media such as isopropyl alcohol, isobutyl alcohol, and isoamyl alcohol, the reaction radius is greater than the sum of the radii of the reacting particles. The long-range character of these processes is due to the relatively weak dependence of the quenching probability on distance.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 25, No. 2, pp. 161–167, March–April, 1989. 相似文献
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Kopranenkov V. N. Makarova E. A. Dashkevich S. N. Luk'yanets E. A. 《Chemistry of Heterocyclic Compounds》1982,18(11):1218-1218
Chemistry of Heterocyclic Compounds - 相似文献